OR use a MCP6001, its rail to rail John Pearson wrote: I'm looking at the LM7101, an SOT-23/5 package. How can I tell from the data sheet if it will work with only a +3.3 volt supply? The input to the amp will be steady-state dc. Thanks ----- Original Message ----- From: "Herbert Graf" To: "Microcontroller discussion list - Public." Sent: Tuesday, August 01, 2006 8:46 PM Subject: Re: [EE] Simple DC amplification > On Tue, 2006-08-01 at 17:26 -0700, John Pearson wrote: > > I need to amplify the signal from a sensor into an ADC. I have very little analog experience or knowledge. > > > > Circuit supply voltage is +3.3 volts. > > Output impedance of transducer is 1K typical. > > Full output voltage span of sensor is 35mV typical. > > Nominal input impedance of ADC is 10K. > > > > I want to amplify the DC voltage from the sensor to the ADC as much as possible. Linearity, temp drift and offset is not too much of an issue. > > > > Can this be done with perhaps a mosfet and a couple resistors? Is there a small package (like a TO92 or 3 pin package) that will do the trick? > > Linearity with just a single mosfet and the range you're looking for > will be an issue. > > Your best bet is an opamp. There do exist op amps in very small > packages. You don't mention frequency response, but you do mention > sensor and the PIC's ADC, so chances are you aren't in the >1MHz range > so nearly any modern op amp with true rail to rail will fit the bill. > > TTYL > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist --------------------------------- Yahoo! Music Unlimited - Access over 1 million songs.Try it free. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist